CBSE2026Class Class 10 · Mathematics1 Marks · Mcq✅ Verified
A bag contains 3 red, 4 white and 7 green balls. A ball is drawn at random. The probability that the ball drawn is <b>not</b> of red colour is :
A. $\dfrac{1}{11}$
B. $\dfrac{3}{14}$
C. $\dfrac{11}{14}$
D. $\dfrac{3}{11}$
✅ Answer & Solution
✅ Correct Answer: C
Step 1: Total number of balls
$$=3+4+7=14$$
Step 2: Number of red balls $=3$, so
$$P(\text{red})=\frac{3}{14}$$
Step 3: Use the complement rule.
$$P(\text{not red})=1-\frac{3}{14}=\frac{14-3}{14}=\frac{11}{14}$$
Step 4: (Check: non-red balls $=4+7=11$, so $P=\dfrac{11}{14}$.)
Correct option is (C) $\dfrac{11}{14}$.
